Hydraulic dredging apparatus

ABSTRACT

Dredging bucket for hydraulic dredging of modules at a great depth, constituted by a main frame on skids, means for bringing the scraped up material into a current of water by the advancing of the dredging bucket and means bringing the nodules cleared of clay towards the hydraulic tubes provided with pumping systems to bring them to the surface.

United States Paten ilundulins Aug, 13, W74

[ HYDRAULIC DREDGlNG APPARATUS 3,556,598 1/1971 Smith 299/8 [75] lnventor: Elie Condolios, Grenoble, France [73] Assi nee: Societe Generale de Constructions Primary Emmi'wr"E meSt urser g Electriques at Mecaniques Attorney, Agent, or F1rm-Cra1g & Antonelll (Alsthom), Paris, France [21] App]. No.: 371,588 D d b k f hd 1 d d f d] re glng uc et or y rau 1c re gmgo mo ues at [30] Fflrggn Ap-phcauon pnomy Data 21 great depth, constituted by a main frame on skids,

J 20, 1972 F H7 .22 9 means for bringing the scraped up material into a curune Mme 2 I I rent of water by the advancing of the dredging bucket [52] US. Cl. 299/8, 37/DlG. l and means bringing the nodules cleared of clay [51] llllt. Cl E02f 7/06 towards the hydraulic tubes provided with pumping Fleld of Search 8 ystems to bring them [0 the urface References Cited 8 Claims, 4 Drawing Figures UNITED STATES PATENTS 532,183 l/l895 Pike 299/8 vv v f1 -e'e'e' t s v v 4:? Y

PAIENIEnwm 3I974 3,929,1 0

sum 1 [IF 3 PATENTED M181 3:914

sum 2 or 3 FIGB 1 HYDRAULIC DREDGING APPARATUS Deposits of nodules of manganese and other minerals are to be found on sea beds at a great depth.

These nodules are often deposited on argilaceous beds and when hydraulic dredging of these beds is effected in order tocollect the nodules, great quantities of clay are brought up at the same time.

The present invention has for its object an improved dredging bucket for such dredging, having the function of collecting the nodules on the sea bed with a variable percentage of clay according to the bottom, of washing the said nodules and of putting them in a hopper in which they may be hydraulically brought to the surface.

The dredging bucket according to the invention is es sentially characterized in that it is constituted by a main frame on skids enabling it to slide on the sea bed, with a device for scraping the said bottom, means for bringing the scraped up material into a current of washing water produced by the forward movement of the dredging bucket towards two lateral wheels having perforated vanes driven in a rotating movement by hydraulic or electric motors, ensuring the washing of the nodules and the removing of the clay, these wheels comprising helical scrapers placed at the base of the vanes, bringing the nodules free from clay towards a central hopper comprising an inlet for sea water, whence they are drawn with the sea water by hydraulic tubes provided with pumping systems and brought to the surface.

The number of skids and their surface area, as well as the apparent weight of the dredging bucket fitted with floats, will be calculated as a function of the state on the surface of the bed, so as to ensure a determined digging in the dredging bucket in the layer of materials to be dredged.

The advantages and characteristics of the invention will become apparent, moreover, from the following description relating to an embodiment for the dredging of manganese nodules on the sea bed, selected by way of an example with reference to the accompanying drawings, in which:

FIG. 1 is an elevational view ofa dredging bucket according to the invention;

FIG. 2 is a plan view of the dredging bucket;

FIG. 3 is a partial vertical section view of the dredging bucket in the plane IIIIII of FIG. 4; and

FIG. 4 is a vertical section view of the dredging bucket in the plane IVIV of FIG. 3.

FIGS. 1, 2, 3, and 4 show a dredging bucket according to the invention, drawn by a cable 1 on the sea bed, by means of skids 2 and comprising a metallic frame 3, a sea bed scraper blade 4, two lateral wheels having perforated vanes 5 driven in a rotating movement by hydraulic motors 6 fed by pressurized water tubes 7, or electric motors. The frame is provided with a plate 11 on the upstream side of the vaned wheel and above it.

The perforated vanes 5 comprise orifices having small dimensions, smaller than those of the nodules and are provided with helical scrapers 8 at their base and a central hopper 9 is placed between the two wheels. The scrapers 8 may be seen more particularly in FIG. 4. A hydraulic lifting tube 10 makes it possible to lift the dredged materials.

When the dredging bucket moves slowly forward on the sea bed, on its skids 2, the blade 4 scrapes the bed and collects any nodules thereon, as well as the clay on the bed immediately upstream from the vaned wheel 5 where the mixture is taken up between the vanes and brought to 12 (see FIG. 3), where the current on the sea bed, generated beneath the plate 11, in the direction of the arrows f by the forward movement of the dredging bucket, passes through small holes in the vanes, drawing the clay towards the back, where it is cast out in the direction of the arrows fl, whereas the nodules, having dimensions greater than the orifices of the vanes, fall to the base of these latter, at 13, where the scrapers 8, wound in a spiral, bring them at 14 into the central hopper 9.

They are brought to the surface, from that hopper, in the direction of the arrows f3 by water coming in the direction of the arrows f2, through the hydraulic tube 10 provided, at its upper part, with suitable pumping means, not shown.

The lifting tube 10 comprises, at its lower part, a discharge valve 15 controlled by a jack 16 which enables the nodules to be emptied from the tube, in order to avoid causing jamming if the pumping stops.

While I have shown and described one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art, and I therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are obvious to one of ordinary skill in the art.

What is claimed is:

1. An improved dredging bucket for the hydraulic dredging of nodules of ores on the sea bed and the removing of clay dredged with said. nodules comprising skids, a central hopper, a main frame mounted on said skids and supporting said central hopper enabling it to slide on the sea bed, scraping means supported by said main frame for scraping the sea bed, means for bringing the scraped up material including nodules and clay into a current ofwashing water produced by the forward movement of the main frame, two lateral wheels having perforated vanes mounted behind said scraping means for ensuring the washing of the nodules and the separating of clay therefrom, means for driving said wheels in a rotating movement, helical scraper means placed at the base of said vanes for bringing the nodules which become free from the clay towards said central hopper including an inlet for sea water, and hydraulic tube means for drawing said nodules to the surface with the sea water.

2. Arrangement according to claim 1, characterized in that said lateral wheels with the perforated vanes are driven in a rotating movement by hydraulic motors.

3. Arrangement according to claim 2 wherein said helical scrapers are disposed on said lateral wheels to displace said nodules toward said central hopper.

4. Arrangement according to claim 3 wherein said hydraulic tube means includes pumping means for pumping sea water through said central hopper to the surface.

5. Arrangement according to claim 4 wherein said perforated vanes have holes therein of a size capable of passing said nodules and too small to pass the clay.

6. Arrangement according to claim 5 wherein said scraping means comprises a blade transverse to said skids and angled to said sea bed.

7. Arrangement according to claim 6 wherein said perforated vanes are helically curved radially outward of said wheels from said helical scrapers.

8. Arrangement according to claim 7 wherein said scrapers are helically disposed in the longitudinal direction of said wheels. 

1. An improved dredging bucket for the hydraulic dredging of nodules of ores on the sea bed and the removing of clay dredged with said nodules comprising skids, a central hopper, a main frame mounted on said skids and supporting said central hopper enabling it to slide on the sea bed, scraping means supported by said main frame for scraping the sea bed, means for bringing the scraped up material including nodules and clay into a current of washing water produced by the forward movement of the main frame, two lateral wheels having perforated vanes mounted behind said scraping means for ensuring the washing of the nodules and the separating of clay therefrom, means for driving said wheels in a rotating movement, helical scraper means placed at the base of said vanes for bringing the nodules which become free from the clay towards said central hopper including an inlet for sea water, and hydraulic tube means for drawing said nodules to the surface with the sea water.
 2. Arrangement according to claim 1, characterized in that said lateral wheels with the perforated vanes are driven in a rotating movement by hydraulic motors.
 3. Arrangement according to claim 2 wherein said helical scrapers are disposed on said lateral wheels to displace said nodules toward said central hopper.
 4. Arrangement according to claim 3 wherein said hydraulic tube means includes pumping means for pumping sea water through said central hopper to the surface.
 5. Arrangement according to claim 4 wherein said perforated vanes have holes therein of a size capable of passing said nodules and too small to pass the clay.
 6. Arrangement according to claim 5 wherein said scraping means comprises a blade transverse to said skids and angled to said sea bed.
 7. Arrangement according to claim 6 wherein said perforated vanes are helically curved radially outward of said wheels from said helical scrapers.
 8. Arrangement according to claim 7 wherein said scrapers are helically disposed in the longitudinal direction of said wheels. 